Fig 1.

Lenalidomide therapy is clinically effective, but does not induce apoptosis of primary B-CLL cells in vitro. (A) Antileukaemic effect [as measured by absolute lymphocyte count in peripheral blood mononuclear cells (PBMCs)] after each course of lenalidomide (Day 7, Day 21) compared to pre-therapy (Pre). (B,C) In vitro treatment of primary tumour cells obtained from B-CLL patients. PBMCs were treated with lenalidomide (Len, 100 μmol/l), vehicle control (Con) or cyclophosphamide and fludarabine (Pos). Apoptosis was measured after the indicated times by flow cytometric staining using annexin V and propidium iodide. (C) PBMCs were isolated from patients prior to therapy (0) or 7 d after therapy (7) and analysed for Bcl-2 family protein levels by Western blotting.